Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b39adab50940b5b…

MALICIOUS

PDF

68.4 KB Created: 2021-04-20 00:44:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-26
MD5: e2d5e79ac45c5a47a074daaa144ac171 SHA-1: 42f645c8580c33473e93716047133b40e734b91f SHA-256: 1b39adab50940b5b1bb62c0d46e184f88564e7ea431e9b4d7a2da36d6762c07e
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to domains associated with link farms and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were explicitly extracted, the PDF structure and embedded links are indicative of a spearphishing attachment designed to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://klm3fg.grhosting.cz/sites/default/files/webform/files/zavemazawutojene.pdf In PDF document text
    • https://www.telluridescience.org/sites/default/files/tstc-applications/kuvusuwube.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/tuwagamutavuvefofufeniz.pdfIn PDF document text
    • https://www.natsihwa.org.au/sites/default/files/webform/dalobasowi.pdfIn PDF document text
    • https://www.ofalloncasting.com/sites/default/files/webform/66890294103.pdfIn PDF document text
    • http://pilgrimland.com/sites/default/files/webform/resume-uploads/41345860665.pdfIn PDF document text
    • https://www.enwidth.com/sites/default/files/webform/resumes/21555212736.pdfIn PDF document text
    • http://cicatsalud.com/html/sites/default/files/webform/kizosilubim.pdfIn PDF document text
    • https://www.osgeurope.com/sites/osg-corporate.dev/files/webform/fifomibap.pdfIn PDF document text
    • https://www.uts.cw/sites/default/files/webform/pugixenarewowu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+make+a+crust+on+pizzaPDF link annotation
    • https://lib.asu.edu/system/files/webform/vabomabexajamoja.pdfIn PDF document text
    • https://printandmail.princeton.edu/system/files/webform/21338807989.pdfIn PDF document text
    • https://www.vub.be/sites/vub/files/webform/piwolumubixu.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce34.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE34 5212 bytes
SHA-256: d9f6e7726543365ae23d7a88ca2021705368da27806d46e81124564a59bd5683
font_01_sfnt_off0000dfef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFEF 10804 bytes
SHA-256: b98ee7b5637499dccaeebf126bdb067e9b5ce8abfc5dcabdf06a897592aeafb6